Location confirmation method and location display system of construction machine and such construction machine

ABSTRACT

A hydraulic excavator periodically measures its current location at predetermined time intervals by the GPS device in an inoperative state where its engine key is in the off position and sends the current location data and time data to a management server by a main controller and communicator. The management server receives the periodically sent location data at its communicator and successively stores it in its memory. The current location data and the measurement time data to provide a location confirmation service by a location information provider. Changes in location can be confirmed on a map, the movement of the hydraulic excavator can be tracked, and assistance can be given for confirmation of location and prevention of theft.

TECHNICAL FIELD

The present invention relates to a location confirmation method andlocation display system of a construction machine and such aconstruction machine, more particularly relates to a locationconfirmation method and location display system of a constructionmachine and such a construction machine enabling the current location ofa hydraulic excavator or other construction machine to be confirmed,enabling a change in location to be confirmed on a map when theconstruction machine moves, and helpful in prevention of theft ofconstruction machines etc.

BACKGROUND ART

Construction work machines such as hydraulic excavators (hereinafterreferred to as “construction machines”) in recent years have been mademore intelligent through the provision of high performance computers andhigh performance programs and have been made able to utilizecommunication satellites, the Internet, and other telecommunicationlines for the transfer information, instructions, etc. betweenconstruction machines deployed at far off work sites and a central basestation (center server) for systemization based on centralized control.

On the other hand, in recent years, cases of theft of hydraulicexcavators have been increasing. Hydraulic excavators are deployed atfar off work sites as explained above. The engines of the hydraulicexcavators are stopped when not performing work and the machines left atthe sites. The machines are not monitored that strictly system-wise.Therefore, they are easy to steal.

Therefore, as a conventional system for reliably preventing the theft ofconstruction machines as explained above, for example, the “theftprevention apparatus and theft prevention system for constructionmachines” disclosed in Japanese Patent Publication (A) No. 2000-73411have been proposed.

This system is a theft prevention system designed to compareidentification information given to a construction machine withidentification information input for operation when operating theconstruction machine and, when judging that the result of comparison isthat they “do not match”, to cut the circuit for powering up the startercircuit and the circuit for supplying hydraulics to the remote controlvalve for running motor operation or the feed path for feeding fuel tothe engine so as to prevent the starter motor from being started up.This theft prevention system uses the special features in the design ofthe electrical system, hydraulic system, and fuel feed system inhydraulic excavators to make the conditions for startup more complicatedand increase the difficulty of theft.

Further, in the above theft prevention system, it is possible to add toa construction machine equipped with such a theft prevention system thefunction of determination of the location of the construction machineutilizing a GPS (Global Positioning System) and preventing startup asexplained above by sending an operation shutdown signal from a sendingstation to the construction machine when the construction machine islocated other than at its predetermined work area. Further, it ispossible to make a display of a PC of a manager of the constructionmachine display a map showing a circle of the work site of theconstruction machine, display information showing the location of theconstruction machine superposed on that map, and enable confirmation asto if the location of the construction machine managed by the manager isin the usual work area. When the construction machine is outside of thework area on the map, it is possible to raise an alarm and send anengine shutdown signal.

However, in the conventional theft prevention system, while it ispossible to make the startup conditions of the starter motor morecomplicated to increase the difficulty of theft, it is not possible tocompletely prevent the theft. Further, while a manager can learn thatthe construction machine has been stolen when located outside of thework area on the map, after this it is not possible to then learn thelocation of the construction machine outside of the work area.

An object of the present invention, in view of the above problem, is toprovide a location confirmation method and location display system of aconstruction machine and such a construction machine enabling theconstruction machine itself to periodically calculate its own currentlocation data and send the current location data and measurement timedata to enable its location and changes in location along with time tobe confirmed on a map when the construction machine moves, enablemovement of the construction machine to be tracked, and help confirm itslocation and prevent theft.

DISCLOSURE OF THE INVENTION

The location confirmation method and location display system of aconstruction machine and such a construction machine according to thepresent invention are configured as follows to achieve the above object.

The location confirmation method of a construction machine of thepresent invention is applied to a system comprised of a hydraulicexcavator or other construction machine provided with a controller, alocator, and a communicator and deployed at a work site and a centerserver provided with a communicator, memory, and location informationprovider. The construction machine periodically measures its currentlocation by the locator at predetermined time intervals in anon-operative state where the engine key is turned to the off positionand sends the current location data and the measurement time data to thecenter server by its controller and communicator. The center serverreceives the current location data and measurement time dataperiodically sent from the construction machine at its communicator andsuccessively stores them in its memory. Further, the center serverprovides a location confirmation service by its location informationprovider using the current location data and the measurement time data.The location information provider is a means for providing an interestedparty such as the owner of the construction machine or manager theinformation relating to the current location of the hydraulic machine.

According to the above location confirmation method of a constructionmachine, the interested party of the hydraulic excavator can immediatelyand easily learn the current location of the hydraulic excavator andchanges in the current location along with the elapse of time. Due tothis, when the construction machine moves, he can accurately determinethis and track changes in location. It is possible to accuratelydetermine even cases where a construction machine is stolen and moved,so the method can be used to help prevent theft.

The location confirmation method of a construction machine of thepresent invention further provides the above such location confirmationmethod wherein preferably the center server is provided with map dataand marks a location based on the current location data and measurementtime data on a map showing an area including the work site of theconstruction machine so as to provide a location confirmation service.Since the map shows the current location of the construction machine, itis easy to determine changes in the current location along with theelapse of time and possible to obtain accurate information relating tothe current location of the construction machine.

The location confirmation method of a construction machine of thepresent invention further provides the above such location confirmationmethod wherein, preferably, in providing the location confirmationservice, the map shows the state of movement of the construction machineas a discontinuous path of location marks based on the current locationdata and the measurement time data. Since the current location of theconstruction machine is marked on the map as a discontinuous path alongwith the time data (year, day, and time), changes in the currentlocation can be easily understood and changes in location can be easilypredicted.

The location confirmation method of a construction machine of thepresent invention further provides the above such location confirmationmethods wherein preferably the location confirmation service prepared atthe location information provider is provided to an interested party(owner, manager, etc.) of the construction machine through acommunications line.

The location confirmation method of a construction machine of thepresent invention further provides the above such location confirmationmethod wherein preferably information relating to the provision of alocation confirmation service is sent to a terminal of an interestedparty by e-mail. As the data communicated through e-mail, onlyinformation relating to the location is sent. For example, it ispreferable to show this in the map information at the terminal of theinterested party.

The location confirmation method of a construction machine of thepresent invention further provides the above such location confirmationmethod wherein preferably an interested party accesses the locationinformation provider of the center server from his terminal through theInternet and confirms provision of the location confirmation servicebased on an advance notification from the center server to theinterested party. In this case, the location information provider isconstructed as a homepage for provision of location information in thecenter server, and the user etc. accesses it from an Internet terminalthrough the Internet to obtain necessary location information relatingto the current location.

The location confirmation method of a construction machine of thepresent invention further provides the above location confirmationmethod wherein preferably the data sent from the construction machine tothe center server includes data relating to a schedule of movement ofthe construction machine and a change in the current location of theconstruction machine is judged to be normal or abnormal based on thedata relating to the schedule of movement. The data relating to theschedule of movement is produced for example by operation of a “nomovement scheduled” button. When judging there is movement from a changein current location of the construction machine based on this data, itis possible to judge if the movement is inherently scheduled normalmovement or abnormal movement due to theft etc.

The location confirmation method of a construction machine of thepresent invention, on the premise of depending upon the above locationconfirmation methods, is a method such that the locator is preferably aGPS unit for measuring a current location by making use of a GPSsatellite.

The location confirmation method of a construction machine of thepresent invention further provides the above location confirmationmethod wherein preferably the time intervals set in the constructionmachine are variable in accordance with the situation. For example, whenthere is no change from the previously measured location, the followingtime intervals are set longer, while when there is a change from thepreviously measured location and theft or another urgent situationarises, the time intervals are shortened and the current location isconfirmed more frequently. Due to this, it is possible to obtain a closegrasp of the location of the construction machine at the time of theftand tracking becomes easier. When there is no urgency, the timeintervals may be set longer to reduce the power consumption of thebattery.

The location display system of a construction machine according to thepresent invention is applied to a system comprised of a constructionmachine provided with a controller, a locator, and a communicator anddeployed at a work site, and a center server provided with acommunicator, a memory, and a location information provider. Theconstruction machine periodically measures its current location atpredetermined time intervals by the locator and sends current locationdata and measurement time data to the center server by the controllerand communicator. The center server receives the current location dataand measurement time data periodically sent from the constructionmachine at its communicator, successively stores them in its memory, andmarks the current location on a map using the current location data andthe measurement time data by the location information provider.

The location display system of a construction machine according to thepresent invention further provides the above such location displaysystem wherein preferably the marks relating to the current location aredesigned so that the state of movement of the construction machine isdisplayed on the map as a discontinuous path of location marks based onthe current location data and the measurement time data.

The location display system of a construction machine according to thepresent invention further provides the above such location displaysystem wherein preferably the marks relating to the current locationprepared at the location information provider are provided to aninterested party of the construction machine through a communicationsline.

The location display system of a construction machine according to thepresent invention further provides the above such location displaysystem wherein preferably the information on the marks according to thecurrent location is sent to a terminal of an interested party by e-mailas an attached file.

The location display system of a construction machine according to thepresent invention further provides the above such location displaysystem wherein preferably the data sent from the construction machine tothe center server includes data relating to a schedule of movement ofthe construction machine and wherein a change in the current location ofthe construction machine is judged to be normal or abnormal based on thedata relating to the schedule of movement.

The construction machine according to the present invention is providedwith a controller for controlling operations as a whole, a locator formeasuring a current location, and a communicator for communicating withan external base station, which construction machine is designed toperiodically measure its current location at preset time intervals bythe locator in a non-operative state where the power key is in the offposition and send the current location data and measurement time data tothe base station side by the controller and communicator.

The construction machine according to the present invention furtherprovides the above such construction machine wherein preferably thelocator is comprised of a GPS device utilizing GPS satellites to measureits current location.

The construction machine according to the present invention furtherprovides the above such construction machine wherein preferably the timeintervals are variable in accordance with changes in the situation.

The construction machine according to the present invention furtherprovides the above such construction machine wherein preferably the datasent to the base station includes data relating to a schedule ofmovement and wherein a change in current location is judged to be normalor abnormal based on the data relating to the schedule of movement.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of the basic overall configuration of a system formanagement of a construction machine to which the present invention isapplied;

FIG. 2 is a side view of a hydraulic excavator to which the presentinvention is applied;

FIG. 3 is a view of the important parts of a communication system of asystem to which the location display system of a construction machineaccording to the present invention is applied;

FIG. 4 is a block diagram of the internal configuration of a maincontroller and the configuration of related peripheral parts in a systemto which the location display system according to the present inventionis applied;

FIG. 5 is a timing chart of the state of transmission of location datafor realizing the location confirmation system and location displaysystem according to the present invention;

FIG. 6 is a view of an example of the data format of location data sentfrom the hydraulic excavator to a management server;

FIG. 7 is a view of the state of change of the current location on a mapwhen the hydraulic excavator is moving;

FIG. 8 is a flow chart of the operation of measurement and transmissionof the current location in the hydraulic excavator;

FIG. 9 is a flow chart of the operation of displaying the currentlocation on a map in a management server;

FIG. 10 is a timing chart of a first example of the time intervals ofmeasurement and transmission of location data;

FIG. 11 is a timing chart of a second example of the time intervals ofmeasurement and transmission of location data; and

FIG. 12 is a timing chart of a third example of the time intervals ofmeasurement and transmission of location data.

BEST MODE FOR WORKING THE INVENTION

Preferred embodiments of the present invention will be explained belowbased on the attached drawings.

FIG. 1 schematically shows the overall configuration of a managementsystem for a construction machine to which the location display systemaccording to the present invention is applied. The location confirmationmethod according to the present invention is applied in this locationdisplay system. In this embodiment, an example of a single hydraulicexcavator 1 is shown as the work machine, and a manufacturer 2 producingand selling the hydraulic excavator 1 and a user 3 using the hydraulicexcavator 1 are shown as elements of the overall system. The user 3 isthe owner, manager, or other interested party of the hydraulic excavator1 and is a customer when viewed by the manufacturer 2. The constructionmachine is not limited to a hydraulic excavator.

In the above overall system, the hydraulic excavator 1 is usuallydeployed at or near a work site at a distant location. The manufacturer2 and user 3 are present at locations spatially and geographically farfrom this hydraulic excavator 1. In this overall system, the hydraulicexcavator 1, the manufacturer 2, and the user 3 are linked using IT(information technology) by provision of communications lines 13utilizing the Internet 11, an in-house LAN 12, or a communicationssatellite 13 a.

The communications line 13 between the hydraulic excavator 1 and thelater explained management server (or center server) in the above is notlimited to a communications line utilizing the communications satellite13 a. For example, an ordinary amateur radio wave, marine, air, or othercommercial radio wave, or general public line of mobile phones can alsobe utilized.

The hydraulic excavator 1 is provided with a controller 14 and acommunicator including an antenna 15. In the configuration of thisembodiment, as shown in FIG. 2, the communicator is provided in thecontroller 14.

The manufacturer 2 has a base station 16 provided with a managementserver 17 and a database 18. The management server 17 is positioned atthe center of this system and functions as a center server. Thecontroller 14 of the hydraulic excavator 1 deployed at the work site andthe base station 16 of the manufacturer 2 are connected to enabledownloads utilizing a notebook PC 19 used by a service staff etc. andtransfer of the necessary information (or data) through an in-house LAN12 or through a communications line 13.

Note that the above PC 19 is not limited to one of the service staff andmay also be another PC such as one for the staff of the user owning andmanaging the hydraulic excavator 1.

The information (data relating to state of operation) generated at thetime of operation of the hydraulic excavator 1 and information (locationinformation etc.) relating to the hydraulic excavator at the time ofoperation and non-operation are all sent to the management server 17 ofthe base station 16 through the communicator and processed and storedthere without regard as to operation or non-operation of the hydraulicexcavator 1. For the information sent from the hydraulic excavator 1,the management server 17 when necessary sends information to thehydraulic excavator 1 and/or user 3. The state of operation, thesettings, location information, and other information of the hydraulicexcavator 1 are stored and managed in the database (or memory) 18.Further, the management server 17 sends to the hydraulic excavator 1 anynecessary information at suitable timings by a one-directional mode. Thecommunication in this one-directional mode is performed, for example,when setting a new version of software or changing settings ofparameters.

The manufacturer 2 is linked with a branch 20 through the in-house LAN12. Therefore, the sales staff or the service staff 20 a in the branch20 can use an input terminal 20 b provided there to access themanagement server 17 and the database 18 to search for data required forwork for troubleshooting or quality information and take it out and useit. Further, the manufacturer 2 is provided with an external use server21 connected to its in-house LAN 12. It can use this external use server21 to provide or present necessary information to the user 3 through theInternet 11 and make various recommendations regarding the method of useof the hydraulic excavator and maintenance. Note that the managementserver 17 of the base station 16 is connected to a separately providedcomputer 22 storing test data (repair and inspection information or partreplacement information). The data stored in the computer 22 is alsosuitably downloaded to the management server 17 and stored in thedatabase 18.

Further, the hydraulic excavator 1 is equipped with a GPS device 23. TheGPS device 23 is provided with a GPS controller, a transceiver, and anantenna. This GPS device 23 is a locator which receives signals givenfrom at least three orbiting satellites 24 a, 24 b and 24 c of a GPSsatellite system 24 and utilizes these signals to measure the currentlocation of the hydraulic excavator 1. The current location is measuredat suitable time intervals deemed necessary. Current location data ofthe hydraulic excavator 1 measured at the predetermined time intervalsby the GPS device 23 is sent to the controller 14 and stored in a memorybuilt into the controller 14 together with measurement time data. Thecontroller 14 further sends the data of the current location andmeasurement time to the management server 17 of the base station 16 atpredetermined transmission timings utilizing the data processingfunction and communications function of the controller 14 and thecommunications line 13. The data relating to the current location of thehydraulic excavator 1 is prepared in the “location movement data format”explained later and is sent as data of the location movement. Further,the transmission timings can be kept as constant periods or theintervals of the transmission timings can be changed in accordance withneed.

In the above configuration, instead of the manufacturer 2, a companyresembling the same can also run the base station 16 where themanagement server 17 and database 18 are provided. A dealer, rentalcompany, lease company, used machinery sale and management company, etc.can be mentioned as such a company.

FIG. 2 shows enlarged a side view of the hydraulic excavator 1. Thehydraulic excavator 1 is provided with an undercarriage 31 running by ahydraulic motor, a top turret 32 where the engine, hydraulic pump,hydraulic piping, power battery, and operator cabin 33 are provided, anda front mechanism 37 comprised of a boom 34, arm 35, and bucket 36. Thebucket 36 is the work mechanism 33 and is freely replaced or changed inaccordance with the work at the user. This hydraulic excavator 1 is forexample provided with the above controller 14, antenna 15, and GPSdevice 23 at the operator cabin 33. The controller 14 is comprised of amain controller 41 and communicator 42. The GPS device 23 is connectedto the main controller 41.

There are actually a large number of the hydraulic excavators 1 shown inFIG. 1 and FIG. 2 deployed at a large number of work sites under themanagement of the management server 17. These large number of hydraulicexcavators 1 basically have the same configurations as that explainedearlier.

FIG. 3 is a view schematically showing the relationship between thelarge number of hydraulic excavators 1 deployed at the large number ofwork sites and the base station 16. The controller 14 of each hydraulicexcavator 1 is provided with a main controller 41, a communicator 42,and an antenna 15. Further, each controller 14 is additionally equippedwith a GPS device 23 mounted at each hydraulic excavator 1. The basestation 16 is provided with a communicator 16 a, a management server 17,and a database (DB) 18. The main controller 41 may, if necessary, haveconnected to it for example a tenkey pad 43 for giving information(content of changes or replacement) to the main controller 41. Thecontrollers 14 of the large number of hydraulic excavators 1 shown inFIG. 3 and the management server 17 of the base station 16 havecommunication lines formed between them by a communication satellite 13a through which they transfer information.

Next, the internal configurations of the main controller 41 andcommunicator 42 and the configurations of their peripheral parts will beexplained in detail next with reference to FIG. 4.

The main controller 41 is provided with a CPU (central processing unit)401, memory 402, input interface 403, output interface 404, andinput/output interface 405. The memory 402 stores a plurality of controlprograms 406 for various types of work operations, operations forpreventing theft, receipt and storage of current location data from theGPS device 23, preparation of the data format relating to the currentlocation, periodic or irregular transmission of the data format(location information, measurement time, etc.) and the data necessaryfor control of the work operations etc. (control parameters andconstants etc.) 407.

The input interface 403 receives as input signals output from the inputunit 44 on the control panel provided in the operator cabin and theplurality of sensors 45 provided at different parts of the hydraulicsystem or electrical system of the hydraulic excavator 1. The input unit44 includes an engine key (power key) 9 for turning the engine on andoff and the later explained “no operation scheduled” button etc.Further, the input interface 403 has a connection terminal 408. Thisconnection terminal 408 may be connected with the above-mentioned tenkeypad 43 in accordance with need.

Further, the above-mentioned input interface 403, as explained above,receives as input current location data of the hydraulic excavator 1measured by the GPS device 23. Normally, it is possible to obtain timedata relating to the global standard time from the orbiting satellitesof the GPS satellite system 24, so along with the current location data,the measurement time data is also given to the CPU 401 through the inputinterface 403. The CPU 401 stores the current location data and themeasurement time data given from the GPS device 23 so as to be includedin the portion of the data 407 of the memory 402.

Further, the main controller 41 is connected to the above communicator42 through the input/output interface 405. The communicator 42 includesa communications controller 409 and transceiver 410. A drive and controlsystem 46 is connected through the output interface 404. The CPU 401gives the drive and control system 46 instructions instructing itsoperation or settings. The operation of the drive and control system 46is controlled based on these instructions or settings, whereby thebucket 36 or other work mechanism 38 provided at the front end of thefront mechanism 37 is made to perform the operations necessary for work.As the work mechanism 38, in addition to a bucket, a breaker, finecrusher, rough crusher, etc. may be mentioned. The work mechanism 38 maybe freely attached or detached to or from the front mechanism 37 inaccordance with the required work and is used as an attachment.

As examples of the control program 406 stored in the memory 402, thereare a program for control for preventing interference in accordance withthe type of the hydraulic excavator 1, a program for control forrestricting areas, a program for control of the posture of the workmachine, a program for control of the operating characteristics of thehydraulic pump (maximum flow rate of pump), etc. Further, in the presentembodiment, the control programs 406 include a program for preparing thelocation movement data format and sending it to the management server17. Further, as examples of the data 407 stored in the memory 402, thevarious dimensions of the front mechanism 37, the interferenceprevention region, and parameters of the control gain, maximum tiltangle of the pump, and engine speed may be mentioned. Further, the data407 includes the above-mentioned current location data and measurementtime data.

The electrical system parts of the main controller 41, communicator 42,GPS device 23, etc. are supplied with the necessary power from a powersource 51 and held in the operative state. Usually, the power from thepower source 51 is input to the various electrical circuits when theswitch 52 is turned on along with the operation of turning the enginekey to the on position. Therefore, when the engine key is turned to theoff position, the switch 52 also is turned off and the electrical systemparts become inoperative in state. In the present embodiment as well,however, when the engine key is turned to the off position and theswitch 52 is turned off or held in the off state, an on control signal54 is given from a timer circuit 53 continually held in the operativestate delayed by a constant time or periodically so as to place the maincontroller 41 etc. in the operative state for a constant time (wakeupstate). Note that the time interval at which the on control signal 54set in the timer circuit 53 is output can be freely changed inaccordance with need based on a time interval change instruction signal55 from the main controller 41.

Next, the location display system and location confirmation method forthe hydraulic excavator 1 having the above configuration will beexplained with reference to FIG. 5 to FIG. 9. The location displaysystem and location confirmation method are useful for confirmation ofthe location of the hydraulic excavator 1 and are helpful in preventingtheft.

In the present embodiment, it is assumed that, at the work site, thehydraulic excavator 1 is in the operative state until 18:00 and theengine key is turned to the on position to supply power from the powersource 51 to the different parts and perform the work. At 18:00, theengine key is turned to the off position and the work by the hydraulicexcavator 1 is ended. In this state, usually the hydraulic excavator 1is left at the work site and the work started again the next day.Further, it is also possible to load the hydraulic excavator 1 on atruck and move it to another location due to a change of the work site,movement to a storage location, or other reasons.

After the engine key is turned to the off position, the switch 52 iskept in the on state for a certain time (for example, two hours), sopower is supplied from the power source 51 to keep the main controller41, communicator 42, GPS device 23, etc. in the operative state.Therefore, the main controller 41 of the hydraulic excavator 1 canmeasure the location of the hydraulic excavator 1 and the currentlocation of the hydraulic excavator 1 can be monitored.

FIG. 5 shows the turning of the engine key to the on and off positions,the turning of the power source 51 on and off, and the transmission andnon-transmission of location data by a time series. The abscissa showsthe time from 17:00 to 05:00 of the following day. As shown in FIG. 5,even when the engine key is turned to the off position (18:00, referencenumeral 61), the power source 51 remains in the on state for two hoursmore (reference numeral 62). During the two hours when the power source51 is in the on state, the main controller 41, GPS device 23, andcommunicator 42 are held in the operative state. Therefore, in thehydraulic excavator 1, even if the engine key is turned to the offposition and the machine is in the inoperative state, the hydraulicexcavator 1 can measure its current location and send that locationinformation to the base station 16 for two hours after the engine key isturned to the off position. In the present embodiment, when the currentlocation of the hydraulic excavator 1 measured by the GPS device 23 is apredetermined distance away from the last measured value (for example, 5km), the location data relating to that current location is sent to themanagement server 17 of the base station 16 by the location movementdata format. Therefore, when the hydraulic excavator 1 is in motion, atransmission is made every 5 km of movement. After the elapse of twohours from when the engine key is turned to the off position, the switch52 is turned off and the supply of power from the power source 51 isstopped.

After this, the timer circuit 53 outputs an on control signal 54 to theswitch 52 every three hours, whereby power is supplied from the powersource 51 to the main controller 41, GPS device 23, and communicator 42.As a result, the main controller 41, the GPS device 23, and thecommunicator 42 become operative and an operation is performed based onthe flow chart shown in FIG. 8 to measure the current location of thehydraulic excavator 1 and send the location data to the managementserver 17.

The operation of measurement and transmission will be explained inaccordance with FIG. 8. When power is supplied from the power source 51(step S11), the GPS device 23, as explained above, measures the currentlocation (longitude and latitude) of the hydraulic excavator 1 utilizingthe GPS satellite system 24 (step S12) and sends the current locationdata and measurement time data (year, date, and time, global standardtime) obtained from the signals of the orbiting satellites to the maincontroller 41 (step S13). The CPU 401 of the main controller 41 receivesthe current location data and measurement time data sent from the GPSdevice 23 and stores them in its memory 402 (data 407) (step S14). Afterthis, the CPU 401 prepares the location movement data format using thecurrent location data and measurement time data (step S15).

An example of the configuration of the location data format is shown inFIG. 6. This location data format includes, as data fields, from thetop, a header, data ID, and record length. Further, it includes a modelidentification code 71, machine number 72, time difference 73 from theglobal standard time, time data 74 relating to the previous measurementof current location, time data 75 relating to the current measurement ofthe current location, location data (longitude and latitude) 76 of theprevious current location, location data (longitude and latitude) 77 ofthe present current location, state 78 of the “no movement scheduled”button, engine status, number of wakeups, internal hour meter, chassishour meter, remaining fuel, mobile phone number, etc.

In the above, the location data of the present current location is sentcarried in the field 77 and the time of measurement of the presentcurrent location in the field 75. Due to this, the management server 17side of the base station 16 acquires the location data relating to thecurrent location of the hydraulic excavator 1 together with the timedata and stores it in the database 18. Further, the content of the field78 relating to the “no movement scheduled” button is data showingwhether the “no movement scheduled” button provided in the operatorcabin was pushed by the operator when the work by the hydraulicexcavator 1 was ended. When the “no movement scheduled” button waspushed, the field 78 carries “1”, while when it was not pushed, itcarries “0”. When the field 78 relating to the “no movement scheduled”button shows “1”, this informs the interested parties that the hydraulicexcavator 1 will not be moved from the work site until at least the nextoperation. Therefore, when the location movement data format having thefield 78 indicating “1” and having the fields 76 and 77 indicatinglocation data of a change in current location is sent, it is possiblefor the management server 17 side to judge that the hydraulic excavator1 has been stolen or another abnormal situation has arisen. Note thatthe field 78 is not essential, but it is useful for quickly andaccurately judging if theft has occurred.

In the location movement data format, the number of bytes, examples ofcontent, and data are shown for the above fields.

The location movement data format prepared by the CPU 401 as explainedabove is sent to the management server 17 of the base station 16 throughthe communicator 42 (step S16). This series of operations is shown inFIG. 5.

The power source 51 is turned on when the hydraulic excavator 1 is inthe non-operative state after the elapse of two hours from when theengine key was turned to the off position and then every three hours(routines 64 a, 64 b, 64 c and the like). The current location ismeasured and sent in the manner explained above corresponding to this(routines 65 a, 65 b, 65 c and the like).

The power source 51 is turned on, the main controller 41 etc. are madeoperative, and the current location is measured and transmitted everythree hours for example as explained above so as to prevent the powersource 51 from being drained. The operation for measurement andtransmission of the current location in the non-operative state of thehydraulic excavator 1 is preferably set to be effective for two days.

According to the above configuration, the base station 16 side canconfirm the current location of the hydraulic excavator 1 at a work siteat a far off position and can make a good guess as to the situation bychanges in the current location. Further, the management server 17 ofthe base station 16 can utilize the location data (longitude andlatitude) of the hydraulic excavator 1 to display the current locationof the hydraulic excavator 1 on a display screen. The content of theconfirmation of location and the content of the display of the currentlocation can be provided to the user 3 etc. through a communicationmeans. The above confirmation of location and display of the currentlocation are performed for all other hydraulic excavators as well.

Next, an example of the location display at the management server 17side of the base station 16 will be explained with reference to FIG. 7and FIG. 9. The management server 17 for example is provided in advancewith map data of Japan as a whole in its memory. Therefore, when thehydraulic excavator 1 side sends location data in the location movementdata format as explained above (step S21), the management server 17stores the location data in its database (memory) 18 as explained above(step S22), then calls up the map data of the area relating to thelocation of the hydraulic excavator 1, displays a map on the displayscreen (step S23), and displays the current location of the hydraulicexcavator 1 together with the time data as a mark matching with thelongitude and latitude on the map (step S24). The location data is sentfrom the hydraulic excavator 1 side every three hours as explainedabove, so at the judgment step S21, it is judged if there was atransmission of location data. When there was a transmission of locationdata, the above steps S22, S23 and S24 are repeated. As a result, marks82 of the trend in current location of the hydraulic excavator on themap 81 as shown in FIG. 7 are displayed as a discontinuous path. Themarks 82 showing the current location display the time data of when thecurrent location was obtained by numerical values. It is possible toeasily determine the state of movement by the change in the location ofthe marks 82 relating to the current location along with the elapse oftime.

When the hydraulic excavator 1 moves, that movement is sometimes normaland sometimes abnormal such as due to theft. This can be differentiatedby the “no movement scheduled” button as explained above. For example,in the case of normal movement where a truck is used to move the machinefrom a first work site to a second work site, according to the displaysystem of the current location utilizing a map, it is possible todetermine where the machine is being moved to at a current time. This isextremely convenient. According to this location confirmation method andlocation display system, a person waiting on site can determine aboutwhat time the hydraulic excavator 1 will arrive.

As explained above, the information relating to the location of thehydraulic excavator 1 (information relating to map showing marks 82 ofcurrent location) is prepared and provided by the location informationprovider in the management server 17. This location informationprovider, as explained above, has the function of providing the thusprepared information relating to the location to the user 3.

In order for the user etc. to obtain this information on site, it isnecessary to inform the user 3, in particular the manager of the worksite etc., of the display of the current location on the map prepared bythe location information provider of the management server 17 in thisway. Therefore, the location information provider preferably is designedto send a map showing the current location from the management server 17to a terminal of the user 3 (PC) by e-mail as an attached file. In orderfor the user 3 side or the site side to obtain the map information asshown in FIG. 7, it is also possible for the user side to access ahomepage prepared by the management server 17 of the base station 16,specify the hydraulic excavator, and perform the required authenticationprocedure. In this case, the location information provider provides thehomepage. Further, a user already having map data may be provided withonly location data and time data.

On the other hand, when movement of the hydraulic excavator 1 isabnormal as a result of theft etc., it is possible to immediatelydetermine this by the content of the data of the “no movement scheduled”button field 78, so the management server 17 immediately sends aninstruction to the main controller 41 side to first further shorten thetime intervals of turning on power and sending location data and makesthe hydraulic excavator 1 measure and send its current location in moredetail at shorter time intervals. At the same time, it is utilized toissue an alarm etc. to the user 3 and track the machine.

It is possible to set the time intervals for turning on the power source51 and measurement and transmission of location data to several types atthe time when turning the engine key of the hydraulic excavator 1 to theon position and in the inoperative state after turning it to the offposition.

According to the time interval shown in FIG. 10, basically in the sameway as the above embodiment, when the engine key is turned to the onposition and the power source 51 is turned on, the machinesimultaneously measures and sends location data. Afterward, when theengine key is turned to the off position, the power source 51 is kept ina state supplying power for a constant time (Tf) for the machine tomeasure and send location data. After the power source 51 enters the offstate, as explained above, due to the action of the timer circuit 53,the power source 51 is turned on at intervals of a constant time (Ti)and the location data is measured and sent.

According to the time interval shown in FIG. 11, when the engine key isturned to the on position and the power source 51 is turned on, themachine simultaneously measures and sends location data. Afterward, whenthe engine key is turned to the off position, the power source 51 iskept in the on state for exactly the time required for measuring andsending location data once, then is turned off. After the power source51 enters the off state, as explained above, due to the action of thetimer circuit 53, the power source 51 is turned on at intervals of aconstant time (Ti) and the location data is measured and sent.

According to the time interval shown in FIG. 12, when the engine key isturned to the on position and the power source 51 supplies power, theconstruction machine measures and sends its location data. Afterward,when the engine key is turned to the off position, the power source 51is kept in the on state for exactly the time required for measuring andsending location data once, then is turned off. After the power source51 enters the off state, as explained above, due to the action of thetimer circuit 53, the power source 51 is turned on at intervals of aconstant time (Ti) and the location data is measured and sent. After apredetermined time, the time intervals are changed to Ti2 and the powersource 51 again turned on to measure and send the location data.

The above embodiment can be changed in the following way. For example,in the embodiment, a “no movement scheduled” button was provided toinform the management server 17 side in advance that there was noschedule of movement by the field 78 of the location movement dataformat, but the fact of no schedule of movement may also be informed toit in advance utilizing for example a mobile phone.

In the above embodiment, the current location of the hydraulic excavator1 was measured utilizing GPS, but if the conditions are right, it isalso possible to measure the current location utilizing a locationinformation system using a mobile phone or PHS.

Further, regarding the utilization of the map information, there arealso web sites providing map information services on the Internet, so itis also possible to utilize that map information for display of the map.

According to the present invention, the construction machine itselfdeployed at the work site has a GPS device or other locator andfunctions to measure its own current location and is designed toperiodically power up at suitably set time intervals in the inoperativestate so as to enable the electrical system to operate, measure thecurrent location, and send it to the center server side, so it ispossible to quickly and easily learn the location of a constructionmachine in an inoperative state. The above time interval can be suitablychanged in accordance with the situation, whereby it is possible toextend the battery lifetime or frequently measure and send the currentlocation at the time of theft or other urgent times.

At the center server side (base station side), it is possible to utilizethe location data relating to the current location periodically sent soas to manage the location of construction machines and possible toeasily obtain a grasp of trends in current locations by marking thelocation data accompanied with measurement time data on a map. It ispossible to provide the location information relating to the currentlocations on the above map from the center server to the user andtherefore the user can obtain an accurate grasp of the state of movementof construction machines it owns or manages. According to the abovelocation confirmation method or location display system, it is possibleto prevent theft in advance and, even when theft occurs, to accuratelytrack the location of a machine and thereby quickly deal with theft.

INDUSTRIAL APPLICABILITY

A construction machine at a work site or other far off locationperiodically measures and calculates its current location data and sendsthat current location data and measurement time data to a managementserver. At the management server, it is possible to confirm a change inthe location on a map when the construction machine moves, possible totrack movement of a construction machine, and able to assist theconfirmation of location of a construction machine at a far off locationand prevention of theft.

1. A location confirmation method of a construction machine applied to asystem comprised of a construction machine provided with a controller, alocator, a first communicator and a power key for controlling a switchthat supplies operating electric power when switched on, and a timercircuit for providing an ON control signal for a predetermined period oftime and periodically at predetermined intervals of time, to saidcontroller, said locator and said first communicator when said power keyis switched off; and a no operation scheduled button for generating dataabout an operation schedule, and a center server provided with a secondcommunicator, a memory, and a location information provider, saidlocation confirmation method comprising: supplying at said constructionmachine electric power to said controller, said locator and said firstcommunicator for operation for said predetermined period of time asdetermined by said ON control signal that is provided by said timercircuit after said power key is switched off, and sending currentlocation data, measurement time data, and said data about an operationschedule to said center server by said controller and said firstcommunicator if said current location data measured by said locatordiffers from previously measured location data by a predetermined valueduring said predetermined period of time, stopping the supply of theelectric power to said controller, said locator and said firstcommunicator, and after said predetermined period of time elapses,periodically supplying the electric power to said controller, saidlocator and said first communicator at predetermined intervals of timeas determined by said ON control signal provided by said timer circuitand measuring a current location by said locator at said predeterminedtime intervals and sending current location data, measurement time data,and said data about operation schedule to said center server by saidcontroller and said first communicator; and receiving at said centerserver said current location data, said measurement time data, and saiddata about operation schedule sent from said construction machine atsaid second communicator and successively storing said current locationdata, said measurement time data, and said data about operation schedulein said memory and providing location confirmation by said locationinformation provider using said current location data and saidmeasurement time data, and judging an abnormal situation of saidconstruction machine when said location confirmation indicates movementof said construction machine and said data about operation scheduleindicates no movement scheduled.
 2. A location confirmation methodaccording to claim 1, wherein said center server is provided with mapdata and marking the location based on said current location data andsaid measurement time data on a map showing an area including a worksite of said construction machine so as to provide said locationconfirmation.
 3. A location confirmation method according to claim 2,wherein in providing said location confirmation, the map shows the stateof movement of said construction machine as a discontinuous path oflocation marks based on said current location data and said measurementtime data.
 4. A location confirmation method according to claim 1,wherein said location confirmation prepared by said location informationprovider is provided to a user of said construction machine through acommunications line.
 5. A location confirmation method according toclaim 4, wherein information relating to the provision of said locationconfirmation is sent to a terminal of said user by e-mail.
 6. A locationconfirmation method according to claim 4, wherein said user accessessaid location information provider of said center server from itsterminal through the Internet and confirms provision of said locationconfirmation based on an advance notification from said center server tosaid user.
 7. A location confirmation method according to claim 1,wherein said locator is a GPS device utilizing GPS satellites to measurethe current location.
 8. A location confirmation method according toclaim 1, wherein said predetermined periods of time and saidpredetermined time intervals are that are set in said constructionmachine are changeable in accordance with a change in situation.
 9. Alocation display system of a construction machine applied to a systemcomprised of a construction machine provided with a controller, alocator, a first communicator and a switch switchable between on and offby a power key for controlling supplying of operating electric power,and a timer circuit for providing an ON control signal for apredetermined period of time and periodically at predetermined timeintervals, to said controller, said locator and said first communicatorwhen said power key is switched off; and a no operation scheduled buttonfor generating data about an operation schedule, and a center serverprovided with a second communicator, a memory, and a locationinformation provider, wherein said construction machine suppliesoperating electric power to said controller, said locator and said firstcommunicator for said predetermined period of time as determined by saidON control signal that is provided by said timer circuit after saidpower key is switched off, and sends current location data of saidconstruction machine, measurement time, and said data about an operationschedule data to said center server by said controller and said firstcommunicator if said current location data measured by said locatordiffers from previously measured location data by a predetermined valueduring said predetermined period of time, stops the supply of theelectric power to said controller, said locator and said firstcommunicator, and after said predetermined period of time elapses,periodically supplies the electric power to said controller, saidlocator and said first communicator at said predetermined intervals oftime determined by said ON control signal provided by said timer circuitand measures a current location by said locator at said predeterminedtime intervals and sends current location data of said constructionmachine, measurement time data, and said data about an operationschedule to said center server by said controller and said firstcommunicator and said center server receives said current location dataof said construction machine, said measurement time data, and said dataabout an operation schedule sent from said construction machine at saidsecond communicator, successively stores said current location data,said measurement time data, and said data about an operation schedule insaid memory, provides location marks of a current location on a mapusing said current location data and said measurement time data by saidlocation information provider, and judges an abnormal situation of saidconstruction machine when said location confirmation indicates movementof said construction machine and said data about operation scheduleindicates no movement scheduled.
 10. A location display system accordingto claim 9, wherein the location marks relating to said current locationare provided so that the state of movement of said construction machineis displayed on the map as a discontinuous path of the location marksbased on said current location data and said measurement time data. 11.A location display system according to claim 9, wherein the locationmarks relating to said current location provided by said locationinformation provider are provided to a user of said construction machinethrough a communications line.
 12. A location display system accordingto claim 9, wherein information on the location marks according to saidcurrent location is sent to a terminal of said user by e-mail as anattached file.
 13. A construction machine, comprising: a controller forcontrolling operations of the construction machine, a locator formeasuring a current location of said construction machine, and acommunicator for communicating with an external base station; a switchand a power key switchable between on and off; an electric power supplyfor supplying operating electric power to said construction machine whensaid power key is switched on; a timer circuit for providing an ONcontrol signal, after said power key is switched off to provide electricpower from said electric power supply to said controller, said locatorand said communicator for a predetermined period of time; a no operationscheduled button for generating data about an operation schedule; saidcommunicator sending current location data, measurement time data, andsaid data about an operation schedule during said predetermined periodof time to said center sewer if said current location data measured bysaid locator differs from previously measured location data by apredetermined value; and said timer circuit providing said ON controlsignal periodically to provide electric power from said electric powersupply to said controller, said locator and said communicator formeasuring the current location at predetermined time intervals aftersaid predetermined period of time elapses and sending current locationdata, measurement time data, and said data about an operation scheduleto the base station by said controller and said communicator and saidcontroller judges an abnormal situation of said construction machinewhen said location confirmation indicates movement of said constructionmachine and said data about operation schedule indicates no movementscheduled; wherein the operation for measurement and transmission of thecurrent location in the non-operative state of said construction machineis set to be effective for a predetermined term.
 14. A constructionaccording to claim 13, wherein said locator is comprised of a GPS deviceutilizing GPS satellites to measure its current location.
 15. Aconstruction machine according to claim 13, wherein said predeterminedtime intervals are variable in accordance with changes in the situation.16. A construction machine according to claim 13, wherein the data sentto said base station includes data relating to a schedule of movementand a change in current location is judged to be normal or abnormalbased on the data relating to the schedule of movement.
 17. Aconstruction machine according to claim 13, wherein said circuitincludes a power key for controlling switching between on and off.